Toggle Button with SpriteSheet

[rSilva28]

I am trying to make a toggle button. So I made a spriteSheet with the two frames with the positions that the button can have.

this.load.spritesheet('buttontog', 'assets/tbspr.png', {frameWidth: 160, frameHeight: 47});

It works when I click it once, toggling it.

        this.buttontog = this.add.sprite(660,420, 'buttontog', this.frame = 0) 
            .setInteractive({useHandCursor: true})
            .on('pointerup', () => {if (this.frame == 0) this.buttontog.setFrame(1); if(this.frame == 1) this.buttontog.setFrame(0);});

What I can't do is to "untoggle" it, and is why I am here, so I can ask for your help. since I am new to this framework. 

 

This is the spriteSheet: